214 Proceedings of the Royal Society of Victoria. 



anterior end, in front of the first complete ring, there is at the 

 dorsal surface an annulus bearing the fourth pair of eyes. The 

 tirst three pairs situated in front of these no doubt represent 

 rings but are not easily distinguishable. 



?» Comfiteh 



Figure A. 



Figure B. 



At the posterior end behind the last complete annulus there 

 are three incomplete rings which end at and help to form the 

 papilla-like structures beneath which opens the last pair of 

 nephridiopores (Figs. 2 and 4). 



Thus there are in all seventy-nine annuli ; at the anterior end 

 three, or their representatives, followed by one incomplete ring,. 

 then seventy-two complete annuli, and behind these, three seen 

 only on the dorsal surface. 



Considering the first three pairs of eyes to be on rings of their 

 own, the fourth pair is borne on the 4th ring, and the fifth pair 

 on the 7th, that is the third complete ring. 



Whitman^ in the paper previously quoted from on the Leeches 

 of Japan calls attention to this arrangement, and says that this 

 absence of a ring between the third and fourth pair of eyes is 

 characteristic of all land leeches. Counting back from the 

 anterior end, there are on the mid-ventral surface two small 

 openings, one, the male reproductive aperture on the posterior 

 edge of the 26th annulus, the other, the female on the posterior 

 border of the 30th. 



It has been shown by De Quatrefages, Gratiolet, Vaillant, 

 and Bourne, as quoted by the latter,- that the annulations of the 

 leech do not represent true somites. These are made up of 

 three or more annuli according to the genus and species. 



1 Loc. eit., p. 3-24. 



» Contributions to the Anatomy of the Hirudinea, Q.J. M.S., vol. xxiv., 1S84, p. 42. 



